Determining the short-term instability of quartz oscillator frequencies

Summary

The measurement results show that phase shift in the instrument depends but very little on the voltages of the frequencies being compared or the sources of supply, thus providing the possibility of using the above instrument for comparing frequencies of crystal oscillators continuously throughout the day and night with great precision.

This instrument in conjunction with the phase shifter can also be used as a phase meter for measuring phase shift with great precision. Thus, the error in measuring a phase difference at 60 kc does not exceed 1 · 10⁻⁴ rad.

If required it is possible to raise the precision of frequency deviation measurements by either increasing the sensitivity of the discriminators by means of larger input voltages to the discriminator, or by multiplying the frequencies under comparison.